Chelsea fans know that there will be a certain day during the current decade where they will see their beloved captain lead out the side for the last time. It will not, of course, spell the end for his association with Chelsea—he may be given a coaching role—but it will be a depressing moment nonetheless.

Because when John Terry turns 33 in December, he knows he will have just a few precious years left in him before the proverbial curtain is brought down on his career.

Replacing the Barking-born defender will be extremely difficult; his leadership and quality is felt both on and off the pitch, and his connection with the fans at Stamford Bridge is admirable.

He has won numerous titles with Chelsea, including three Premier League titles and has a Champions League winner's medal to his name. So to follow in the footsteps of Terry will be a tough task for his replacement.

Could it be a rising star at the club already who can take the reins over from the former West Ham trainee? Or is a big-name signing required?

Come find out who we think can lead Chelsea once Terry has hung his boots.

David Luiz

David Luiz is an enigma for journalists and pundits. Why? Simply because they cannot find a suitable word to describe him.

On the one hand, Luiz possesses an unrivaled ability to read the game which enables him to make crucial interceptions.

However, despite his flashes of brilliance, this is often combined with an extensive list of errors and mistakes, and there are times where you think about whether Luiz will fully mature as a player as he approaches the prime years of his career at the age of 26.

The Brazil international, who joined Chelsea from Benfica in a deal worth £21 million two years ago, has experienced many highs and lows already in his career at Stamford Bridge, such as winning the Champions League Final in 2012.

His leadership qualities can not be questioned, though, as Mano Menezes handed him the captain's armband for their friendly against South Africa last year, highlighting his passion and determination when he steps out onto the pitch.

Luiz has already improved drastically since his debut for the Blues, and as he approaches his 100th appearance for the club, he would be the prime candidate to step into Terry's shoes once he leaves.

Hector Moreno (Espanyol)

One of the lesser known talents in European football, Hector Moreno has made quite an impression on his travels from the Mexican town of Culiacan.

Starting out at UNAM Pumas, he earned a move to AZ Alkmaar in 2008 after starring in the U20 World Cup with his country Mexico.

And from there, the towering center back has gone from strength to strength. Moreno made 87 appearances for the Dutch side as he spent three seasons there, winning the Eredivisie title in 2009 as well as the Dutch Super Cup.

A full Mexico international, the 25-year-old represented his country at the 2010 World Cup in South Africa, playing in the famous 2-0 win over France. From there, he has made 41 caps for his country.

Now plying his trade for La Liga strugglers Espanyol, Moreno has really caught the eye this season with a string of impressive displays. With confidence on the ball as well as a physical presence in the air, he would certainly fit the bill should Chelsea look to replace Terry externally.

With his whole career ahead of him and available at a price of just under £10 million, he could well be a suitable candidate. However, they would face competition from Barcelona, who are looking for a new center half to replace the aging Carles Puyol.

Nathaniel Chalobah

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There is a reason why Chelsea are so keen for Nathaniel Chalobah to impress during his loan spell at Watford, which is managed by former Blues legend Gianfranco Zola.

That reason? Because out of the players that have come and gone in their side, the only academy products to truly make an impression have been John Terry and Ryan Bertrand. Other promising prospects, such as Jack Cork or Michael Mancienne, have gone elsewhere to ply their trade as chances at Chelsea became limited.

But there are high hopes for 18-year-old Chalobah, who has been a regular feature for the Hornets this season, impressing in a more advanced role in central midfield and has scored four goals, this in 33 games.

However, as a natural center half, he could be one of the options to replace Terry. Despite already being an England Under-21 international, Chalobah is yet to make his senior debut for Chelsea.

But high recommendations from youth team coach Dermot Drummy could mean the Sierra Leone-born defender may be given a chance to shine in the 2013-14 season, with a view of being integrated into the first team fold.

For now he will be focused on helping his temporary owners gain promotion to the top flight. But mark my words, Chalobah will be a star at Stamford Bridge for years to come.

Marquinhos (Roma)

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When you watch Marquinhos in action, it is beyond belief to think that the Brazilian is just 18 years old.

But the Roma starlet, picked up by Zdenek Zeman from Corinthians last summer despite just six senior appearances for Corinthians, has rapidly improved since making his debut against Bologna in September.

Forming a decent partnership in central defense with his former teammate Leandro Castan, Marquinhos has made 22 appearances in the Giallorossi shirt, and his performances have not gone unnoticed.

Stefano Denswil (Ajax)

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One of the surprise names on this list, it's extremely unlikely you would have ever heard of Stefano Denswil unless you avidly follow the NextGeneration Series.

Denswil captained Ajax in the Final of the competition—which has been hailed as the youth version of the Champions League—against Internazionale last season and scored, although the Italians ran out 2-1 winners.

His performances for Ajax's Jong side did not go unnoticed, with the first team coach Frank de Boer selecting Denswil to start in a KNVB Cup game, where he scored on his debut. And after impressing against ONS Sneek, he made his full debut in the Eredivisie in the 2-0 defeat to Vitesse.

Only 19 years old, Denswil is just one of several bright prospects off the production line at Ajax's famed academy, where has been since he was eight years old.

A center back primarily, he can also play on either side of deense as he possesses great strength and pace. His aerial ability is outstanding, and in a similar mould to Vincent Kompany, he is a powerful player too.

And as well as being rated highly by coaches at the Dutch club, it seems Denswil may want to stay at the Amsterdam Arena for years to come. However, with the likes of Jan Vertonghen becoming a success in the Premier League, it may not be too long before clubs such as Arsenal and Chelsea are scrambling for his signature.